Anistardi Peletuk

[thimios]

Anistardi Pelatuk Amplifier

I have promise to bimo this test.
Diy pcb of course...
Photoresist method.

 

[AKSA]

A very nice design....... I will be very interested, Thimios, your thoughts on the sound quality. It has VERY low THD, of course.

HD

 

[thimios]

A very nice design....... I will be very interested, Thimios, your thoughts on the sound quality. It has VERY low THD, of course.

HD

I hope so Hugh, it is my first touch to bimo's amplifiers

 

[dadod]

I hope so Hugh, it is my first touch to bimo's amplifiers

Is this one with OITPC?

 

[thimios]

Is this one with OITPC?

Yes, according to bimo answer.

 

[audiofan]

Is tis your first job done with PCB ?

I did a lot of work with PCB yours is great ... but try to reduce the diameter of the holes in the copper foil .... as small as you can only to give a center to start the drill bit, then you will keep as much copper as possible ... soldering will be easier and stronger.

 

[thimios]

I am not the PCB designer,i have etched and pierced this only.

 

[thimios]

Small progress.

 

[thimios]

A little farther.

 

[stocktrader200]

Thimios, I thought you built a tribute 3000 type amp.

 

[JMFahey]

Just checked Anistardi´s site to check the schematic.

I find it weird and counterintuitive that the thermal sensor is a mid power transistor (BD139) but power transistor drivers are flimsy TO92 low current transistors such as 2N5401/5551 , quite unsuitable for the task.

 

[AKSA]

JMF,
The TO92s are rated to 625mW and should do reasonably as drivers IFF the rail voltage is no more than 42V. I agree, they are pushed, but I have found they last OK at low power and particularly if the outputs have high beta.

Can answer for Bimo but the BD139 makes a great temp sensor because it can be bolted to a TO3P, a convenient thermal connection and quicker than on the heatsink.

HD

 

[anti]

For sure a TO126 is a better package for thermal transfer; much easier to mount ...

 

[thimios]

I'm close to finish but i ended up from 330R.
May be two 680 in parallel....
Second problem,i haven't any solution for pcb cleaning now...

 

[AKSA]

Isopropyl alcohol, or Methylated spirits if you have none...... but needs to be brushed after to remove the misty, white residue.

HD

 

[thimios]

Finished, tested but strongly distorted sound.....

 

[thimios]

I will start for the troubleshooting.
Bimo,is this pcb a tested one?

 

[thimios]

More photos.
Where is bimo?
Is it a tested pcb or i must check for errors?
I see 0.5v across R22.

 

[thimios]

Problem solved.
My tragic mistake...
This is the first time that i solder a wrong resistor.
I'm using a, 2K2 instead of 22R....
The voltmeter discover the fault.

 

[AKSA]

Good find, Thimios, these tiny mistakes are very hard to find........

Hugh